Stevia and Stevia Extract - The Facts, Safety and Benefits

Updated: 06/25/2017

What is Stevia and Stevia Extract?

Stevia extract is a naturally occurring sweetener extracted from the leaves of a sub-tropical plant species called Stevia Rebaudiana Bertoni, or more commonly just Stevia. The plant is native to South America, where the sweetest plants grow in Brazil and Paraguay. Since stevia extract has become commercialized, however, it's now grown in multiple locations around the world besides just Paraguay and Brazil. The United States, Kenya, China, Vietnam, Argentina, Columbia, India and other countries also grow stevia where conditions are suitable, and it's a sustainable, natural and non-GMO crop. The compounds in stevia leaves responsible for the sweetness are called steviol glycosides. There are at least thirteen steviol glycosides that can be extracted from stevia leaves but none are as sweet as stevioside and rebaudioside-A, with rebaudioside-A being the least bitter and having the sweetest taste of the two [1] [2a] [2b]. Rebaudioside-A can also be referred to as rebaudioside A (without the dash) and Reb A or Rebiana [11].
There are numerous patented methods for the extraction of rebaudioside-A dating back to the mid 1980s. Some of the original extraction processes from the mid 80s to the early 90s used hard to filter and undesirable chemicals for leeching out steviol glycosides such as chloroform or hexane, but have long since been replaced with much safer, effective and cost efficient methods (at least in the USA and EU). In brief, the most common commercial extraction processes, which are safe and approved for food-grade rebaudioside-A production in the USA include:

Nearly the exact same process as method 2 but methyl alcohol is used instead of ethyl alcohol.

A process that uses already refined rebaudioside-A, and processes it again using an augmented version of method 2 above

All major/commercial USFDA approved stevia-based products available in the USA, whether it's contained in a product marketed directly to consumers or a bulk product marketed to businesses that produce stevia-based products for other businesses, use one of the four modern processes just mentioned. [2] [3] [5]. New extraction methods and methods of combining various steviol glycosides to combat the inherent bitterness of purified rebaudioside-A are being developed and will be hitting the market between early 2018 to 2020. As more detailed information becomes available this article will be updated to reflect the new methods and steviol combinations [4].
In a majority of off-the-shelf stevia-based powdered sweetener products you'll see in the marketplace, there will be some type of bulking and flowing agent added to the powdered rebaudioside-A to make the final product easier to use for the average convenience-minded consumer [11]. The reasoning behind this is due to how little stevia extract is actually needed to equal one or two teaspoons of sugar. For example, stevia-based sweeteners in those familiar single-serve paper packets without bulking and flowing agents would be so small that many people would have a hard time opening them up and using them, as the packets would be about half-inch square or smaller. The bulking and flowing agents listed on the product boxes from the various popular stevia-based sweetener manufacturers can be any of the following:

Iinulin (a natural prebiotic and form of dietary fiber derived from the chicory plant)

Dextrose (a form of glucose usually derived from both GMO and non-GMO corn, tapioca/cassava root, rice and other starchy plants)

A growing number of popular stevia-based sweetener companies also offer just rebaudioside-A powder or liquid for those that dislike any added bulking and flowing agents or want to create their own mix. While there is nothing wrong with buying purified rebaudioside-A powder or liquid with no additives, I do not recommend buying it from unknown sources, companies with no reputation, history, or proof that their product is fit for human consumption.
For those of you that like to consume foods in their natural state, it's entirely possible to grow your own stevia plants, then dry and grind up the leaves for use as a sweetener, garnishment or to steep in various teas (you can also boil just the leaves to make plain stevia tea). Stevia leaves are also sold pre-dried and/or pre-ground, but if you're going to give this a try please make sure you buy the leaves from a reputable company that specializes in handling natural foods in their natural state. AND, also be sure that you are not allergic to stevia leaves in their crude or natural form, as not all of the compounds in raw stevia leaves, aside from the steviol glycosides, have been fully researched for the safety of daily consumption or allergic reactions.[11].

Is Stevia Extract Safe?

Yes Stevia extract is safe to use as long as it has been extracted using an approved method as described earlier in the article and it's from a reputable source. Extracted rebaudioside-A is the exact same steviol glycoside that is in the leaves of the stevia plant it came from, that's why it's called an extract and not a "derivative, reformulation or reconstitution". The leaf is processed to separate and isolate the rebaudioside-A from the leaf and other steviol glycosides, but the glycosides themselves are not processed or modified. Think of it as panning for gold - you have to filter out the unwanted debris in order to isolate the gold - the same principal is used when processing stevia leaves, albeit a far more complex process. It might also ease your mind to know that on the more scientific end, rigorous testing by independent laboratories of the purified form of Stevia extract (specifically rebaudioside-A) that is 95 percent pure and greater has shown no evidence of any toxicity, carcinogenicity, or other harmful effects in either animals or humans [6][7]. Consequently, Stevia extract for use in food preparations and as a sweetener is FDA approved and actually has been since late 2008 [5]. In addition to the USFDA, the World Health Organization also agrees that Stevia extract is safe after reviewing the credible evidence of these various independent studies [8]. Rebaudioside-A by itself is also safe for pregnant women according to the American Pregnancy Association, but there is no mention about whether or not it's safe to use while breastfeeding [12], so check with your healthcare provider on this issue (if I find reputable study information, I'll update the article accordingly).

What Are The Benefits of Stevia Extract?

Stevia extract doesn't get metabolized in the stomach; instead it's metabolized by the natural bacteria in the intestines and passed on as waste (both types of excretory waste) so it's not absorbed as glucose into the body. Because it doesn't get metabolized as glucose, stevia extract doesn't raise blood glucose levels and is considered sugar free and calorie free natural sweetener [9]. It's approved by the American Diabetes Association, which has declared that all nonnutritive sugar substitutes approved by the FDA are appropriate for diabetic friendly diets [10]. But, there are those added flowing and bulking agents used in commercial stevia-based powdered products which often do have some type of sugar. However, the amount of sugar in the form of dextrose, maltodextrin, erythritol, etc. in each packet is so insignificant that blood sugar levels are not affected, unless a massive amount of the product is consumed at once. Being 100% sugar free, Stevia extract itself doesn't promote tooth decay like regular table sugar does, which is an often overlooked bonus. One last benefit to note is that adding or switching to Stevia might also help you diversify your diet if you've been shying away from foods that require a sweetener or are less than impressed with the other sweetener choices on the market - it might just open up some new doors for you.